SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7e9b497ab00f72318030bea7dffbd9198e447862b62a0823d93ee099d54857f5' 
  AND token = 'U6tV/vQK1gDT2RCZMJcjMiQ/ukXf1eCSI8zV1SBxiyg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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