SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '77c65e12203ecd26086cceaa0d5a8f7973fa25f651a86795251af31a6d0cef27' 
  AND token = 'NIzJpg4Jx6rRF9dhHsz/62Ng00ctirgF8mWz/Fmn1rs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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