SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b63ee4b5f3835f9755d2d010093f05b7087bcf0caa30efa2e29d2018f7ed84fb' 
  AND token = 'sOuOEAsUqI/1Kv0gG4YCFR96EANBQK/N6+8w08a8ljU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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