SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '27a25549fae66ad326f86370ab31d770ebd27d52c9809a01af76a9e2bafae3eb' 
  AND token = 'rTzz24H5V24K228rQjpT/CitR02KZr49XQvgEovHNzw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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