SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cfefb1595f93ef77231b99614eb3db5c9a06e375fa5aba27aa8b4202aed395f9' 
  AND token = 'P++jNzeDtpFKPosuPMrUqf7HKyQYtwNGIJlGhPcFSTs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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