SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e3d9ba8f015ad1bd288a9152b0e2d83831bf06481db15e936f2d42aca2360f6c' 
  AND token = 'R1TdF0e2EzsscvUSGQEh//EG7PB1s69PZHyQyavUmdw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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