SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e72f40a67352fb97f777bd081be9158937cb65d13e3f872feb0cc83fc43bf34f' 
  AND token = 'fM9S+DMnFF7qHY42n/DeCZy+QwX/SlY8ZgphKIiE/2w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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