SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e1dccc3159459b47f51a5be6fca607f3bafc9e9b4447d62de385215a77d3b373' 
  AND token = 'TY/HnBZJY6yVFKGK1AAbXv9PvYeSAzjGRt265KLozls=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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