SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5f0a1d3a9159aea568e0b43b99bb8a9ed865401a2cc0984dc8180ddddf1048cf' 
  AND token = 'vlUmXmXRgmgUI0S40D2UW5QwcEm1SkLr0FTijIDauBE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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