SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7efd047bcd976f054cb28ed3a565e117f471552ac0ac923a67454bd1dc0b41c9' 
  AND token = 'F+JKaSxW2ju39KFsDZLq/qBew4Q+LjlcS+1YdUUiqdk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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