SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd9bfdb6391904315c78d4055bf5bdce1084fcb0d82dc8639a835ebf99b024eb' 
  AND token = 'QMxTj8vOejqHmSNFR8uU5Gl3Fks5/WORsUJFMR7N1Zc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00010

JSON explain

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