SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '7475b6c6b099bae610220427ae38139c20fe2aa476e4bb6f3792a17ea447ce56' 
  AND token = 'cp/c+rjKtqxLHYPM0EvzvO8YyYsfkdvW4r5bNPgMWGs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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