SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '6c461e475021f18f2fc16931d3b37326b6326ecf600bb6a1d049f17a6cef8b02' 
  AND token = 'ZZFH5OyaltCFieCjm92nPIL+G4p0ymeXAVp7tIwwKzM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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