SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fec07399da2b88acadd56c0789c4af7a38497f082f5272e3b7263294ede9847b' 
  AND token = 'EtFYw1t0gm/IFNBnfBYamShHEJLKz/droKBarqMFB0g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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