SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45b32556333aefb39dc199ef7214a619deb2ea60934a87c9814c1f4255d82d4e' 
  AND token = 'gB9vKGJtT5qh2IkZqXpJ+ZPZBBTtM/F0O+mXbzXJLVY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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