SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14694f1b27a0a602c9f82b5825d9bde31b2d447515e6873d1737f614ccc463d3' 
  AND token = 'zFkKVRPLCk7sUSPQ/VCXkRngLw+uMmHGSm8lgPWK5SU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}