SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce77186406ba177e5c3ce226467bfd0316abce8bf57c8c1b57fff39202c565e8' 
  AND token = 'h6rz/dL0z8BOONinXBRJgvqKOCG3RTP3GHQbLaiLdkw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00012

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}