SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60e4a72e2a80910a2d4270436adb26d2d31b79b9385588cf95970760fb3c6dcd' 
  AND token = '56l16O+9kyqlRR2EEpTtM6/nm6jgMYA1kMi0zPeLkHI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00061

JSON explain

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