SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f5d238b1c49dc9f888848c0ce8c107b9cb726426f244fae195b7848138d5fcf3' 
  AND token = '1svKhTBASHYtqupW5rzV5wjzq4oXRGdUD5HMgn4yUB8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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