SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '676d79147aabb794a45010b0c2d16499e185711490cc59089ce9bd2a3fcdcde5' 
  AND token = 'H53mtniJUuokVYlW0tVnCaST7vW1YYgwQqSS8Yb75x4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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