SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e23044d1bc7fff7ebc70d5cf0be93cb188a2272aee7826db29c6aba1622b0137' 
  AND token = 'ZvcWDijSIenH6Gdjwas3CdvmEjfSvmF7azdxMPmaYxo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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