SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '20b31e1072c71a8a898ef92358df7842281f4e96a565d0949dd293dd94865501' 
  AND token = 'jS6Ppz3IRkqMXdpEz0AGg+1+B+3hMRF5ZRPi/UB1LK0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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