SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '86499913a41335697f87508b2de6a5be9c1530d9f0d84142d03199e91c8e40bd' 
  AND token = 'DO+GDdjEbvrg73cKcV5j7/QRXLeg/ZQeaZBQZXBnLjg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00063

JSON explain

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