SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6abf0530b2268bac944387f55a41195f69b14932be51cea98792b8df39a592e7' 
  AND token = 'XpwD4mY6tWnql7FSt5+LlvKr6WS1gAS66kVBnZA+uhs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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