SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1780375b6346d8c2bfa4d12a6e092d4f3fea5f7f62c3e8a9fb33505dc0808631' 
  AND token = '4bUbvNTqTITovhzzaQhf26puBWxWwOq+0h8j1ITmOf4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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