SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b0f7d9820f1df859da628e2d4adf048c9a826c3d9dc81b337181cd0e72050da6' 
  AND token = 'mbB+VHDA1J+x5a1/UxDZCfGLAwiwOvSVu/PFLvWyvZo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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