SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3256a1bc4cb8fcda8e3d890026c7c963b7131c98aedf39e855252156376b61f7' 
  AND token = 'qOUViAPThVY8DZh00yaqVFSGEip/3Yd5QU/m9wcrMN4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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