SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a30314d56d210ff0eaa2bec6ab410d296b147fb5df8f0a45a4577d4ac3318ee4' 
  AND token = 'aYuZyO9rxvb4LHELmUzdQBBUCbSzV0FQqkqDKWBThsU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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