SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '28abc7f7a176e6170fff7b1058db3daf5ad66211f4f3434d97af9e9fdb444529' 
  AND token = 'HXDoYLfzrqJjrnAxhVtD9fXnpJDlP4me899YX84Z7bc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}