SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1c7c8f32e3623342a591f2551aeb4bc1f49de7c919842b2a02f98b422b88a81a' 
  AND token = 'bzmUB/3e+Rjx/q4aKP0XtJOM3oZEusAzt4mZnWkI8G8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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