SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '35087960494dabe79391ebd2a9f3c872949dc62c9eb33194986d17ef232f489e' 
  AND token = '8htHZQ7r8fOOBrIgvartdnD/qFw0Ftoe5ZA5xwGylI0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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