SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3a44fe3ae7ce660d0bbfd3a2026f0de4cdf51fe327a97777a18d8c15c8994480' 
  AND token = 'URYNkJ8ygxi1hA0KGfH+gyW1VW7yQuRl9atVP9SLdvg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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