SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e52470de037fdc70d2a83a1d48e7ec9cbd47eab2dd72c2c1968f7f19fc47d25e' 
  AND token = 'k24G2K4PyFDzcKzdnUJeD9LzmuLgrMqpnsq7Ph5kUaM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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