SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c8f8ea5650d54bc6254cb406600719541a118469007ea9c0871ef2c656a74201' 
  AND token = 'iipoz7FA9u5+pXEUJCPsYt0+BZ12HJZH8vdOOrqFMrE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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