SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3906fde48c43dabdbecb7a60fbf957448925a3f8c18eea1aa3364a0381416f35' 
  AND token = 'jNWeFPsaxYXLXzogNFze0UdKeTIQfDY13jAWm5tGptc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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