SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2426770d68af8b603dacb7d530f294dfbfc6a3105668848ac30bd4efa78b266f' 
  AND token = 'XZuYLpcHxIjdLnYPRjRbTxV60liqG7pGNj5vVGaM4Jc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

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