SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e08acbf405dc254e6406c0c33101b4da113d04b6b029e3b4df3f0e83f1f75872' 
  AND token = 'e0k9SY+GkkvevUsXoZlf1Br8q+XiN+upKErzd/OciVs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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