SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'adf3415955f28ee1453990a63a0c2e87ed5bdea932261fa9a43346cbc7b20f5f' 
  AND token = 'dTljquy/kpuDnsYhLIwhHfVjEv/Jo5nW0ovz7aDkKdE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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