SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fefd269748de1ebf33337f0cc26916b581213feadbca4e65be89b97588b550ac' 
  AND token = 'PD/ssaiuyA0/2ZX7YJk+m4wEF8kp9L4vYr9sORi9ryo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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