SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b1054046bfbafe7a728eaffc75172567735d6db7632d80bd73722e49a1f9eda0' 
  AND token = 'I1grTVJ2vRmkLABxTJu3w7Q5QOChXDDjvXs/gKRM0kM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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