SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9fb1d34ab0ed066d468517766399628e8459b6c809c177426ff062c513cc17cb' 
  AND token = 'BKSVdaBxnzr+R2jCnAR4oHhV9Q9RKhp5IKTgG5P57cQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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