SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '748c8e845c46797265c9e9e045ceb15e3e8aa2f91d36124b57d483b5667fce2b' 
  AND token = 'zSNT8aji2j0wLYKrlt2oBbO51woXFz9wrPBqwmPYh/g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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