SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '95766a6e5251deac92cdead7aaa1cd370dd196c4e5608d62e190f509c581faab' 
  AND token = 'C96n4E6Yw5pG6+nRlQTqedpS8MrrxfWMNJq9kNlNnh0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}