SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f11ba8b31b9493b630a5b83ca503491e37bf58776353e8fcf96247cbb74388d6' 
  AND token = 'Tjy7IIXSANFqwY/GJsgEAe4zLgJnFiTJSGzOiDPg8z8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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