SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '25c8f9542b7c5ad52f374184afafabce7db50c249b4230f00513eb7321f87ebf' 
  AND token = 'X3OIP57Tf+/HQqr/iBziP1rJSZ6bkZSmTUjDOiVEd18=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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