SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'd7560a86a80fb1a6cb51e56d94dbceada381ef10225ed62bcf6b87e567f0c518' 
  AND token = 'XdDYo0y+Z8FZXwRWJuxLoZjj9Ig6qrRq/I5rTQdkjRw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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