SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '530d75337c5be4a11d2038287f094a3b1afc75b3e8051bc8522d745fc8be4839' 
  AND token = 'FAngYBj2vhmUL5473JUDFCpIz9byb+ujn+c8uXvJ7MA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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