SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d2f89f9082356e7fbd1a5b13a4b913d3513d4688424632c8f1614f444c3f8fd' 
  AND token = '+zLZGF+DbHorwwMGUYZemcBdYKZBJpiOxvzNrRrsObU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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