SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '137034b76820da385410330cc11e252f656a4f043a2bb8a42f589fc3cf4e2dae' 
  AND token = '3fIFKXPNnzGLAOGOzuBHiPfbyihu9lYHCl7CvXTNKyA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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