SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ba433b52ef8cecb684d3a9e08808e0a8bc403c9f0880c9ae85998905b38b770' 
  AND token = 'Zlejw2H9qblGsIPNeADr0R7SXpLO3yq5DhFuJfahuKI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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