SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bf7b643a12c2120e6912b1032019155fd1f1e22f2ec51042b190835c87540bf1' 
  AND token = 'K1ZGnD7/xgfuFgyufQymEluclbZ2Mr1wcZBYFgPiFM8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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