SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e935056eea496dd5faae02014ef176dc8e976fc82a666a3aaf233cb61dcae9f9' 
  AND token = '7wYTit2EJnBFMKyA+Bda8Wq5M0hqpHsktxBcGdr+HV4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00076

JSON explain

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