SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c13c14f13c848c8ce642ec80ae9d2e6405cab1594c59c0feecfa9f9d3bb71b90' 
  AND token = 'nmc7VUL7WywJ67+oGEYMSsq7oIZuBPHrUzSVxD/WR+c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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