SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dc07991a0409119393adfd213d1cf19fa4965ed5c00564bdf78d4e6f23e56cf1' 
  AND token = 'jZfqjRjaLphpzf3mufVoPPaa6GiB2WeVkDPPYR60do4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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