SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3ee5d2f024697c9c383ab5946dec84e884ab21b555c4ed3c72de32e5f998f20e' 
  AND token = '9u3jOs/N6Pz9hAsRngRrhsPq/lPqkuYAkJ+bV7Eoe1I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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