SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '964893a61b79e23556cac881574bec0d81eb5049d6fa160a3317e3f0f7c90ac9' 
  AND token = '+qud3+Y3jHH0jmEhxQRp2/hol5NeuAeTmHNg1ezDjIQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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