SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6d5ae5f903e3f94b952ebd7b1da0408c82de229746271883d3a217b3d3250afb' 
  AND token = 'tZDWMHHi0+tR2udmF4NXJ3yyQFLPGRLQdKy0TbT6Ddk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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