SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '452e60b1e7936fe670a1589bd16aab18edc6dcf9e7bfd0ba17d61bcf5a51dd23' 
  AND token = 'dvHXC0lqLpgfzudKyMon6avXXhA9yaOfK6JBIOBzoQ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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