SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c2f039a5057028635ef2f1a610f5e734dd403b16807c04bf8fc9291810dc7ae' 
  AND token = 'SUTXYdggF8+vkD3eJTIsubNfKd/IXEPf2fsOgQVTHRI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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