SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fed93b8acc63a2b0885cf788e1d2f67f62dc1a2f777355f8fcad3f57a65448fc' 
  AND token = 'zQc0l2YqcwIeZ5UzfQDO6W+hwND4gTWKZyCPzu59OU4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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