SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7695289edeb51f6f606d5071586b6ddad7e60c1c58d0991380b55362f521e84c' 
  AND token = 'fGvUTy0ZcWLiaPWBSULg1ffIyXmxmcdq0e2nfgonGmM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00070

JSON explain

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